Twin Cities hospitals were packed and Minnesota kids cooped up in the summer of 1946. Not only were swimming pools and movie theaters closed, the Minnesota State Fair locked its gates during the state’s deadliest polio outbreak — nearly 3,000 cases that resulted in 226 deaths.

Polio struck children especially hard in 1946. More than 70% of Minnesota’s cases and half the state’s deaths hit those under 15. Spreading mostly in the summer months, the polio virus festered in lakes and pools and attacked the brain, spinal cord and muscles. Often too weak to breathe, some patients were locked in iron lung machines that kept them alive with only their heads exposed.

This was before the advent of TV, let alone Zoom platforms and social media. At the peak of the crisis KUOM, the radio station at the University of Minnesota, jumped into the void to lighten quarantined kids’ burden.

“Parents grew weary as their children, lacking entertainment and activity, became agitated while stuck indoors during summer vacation,” Rebecca Toov, a U archivist, wrote in a 2016 web post on KUOM’s service in the 1946 epidemic.

The roots of KUOM date to 1922, when its precursor received the state’s first broadcast license, becoming one of the nation’s first radio stations. Today, after a merger with another campus station, KUOM is known as an alternative music station called Radio K.

But during nearly seven summer weeks in 1946, the radio station devoted more than 150 hours to children’s programs, roughly one-third of its schedule. Civic groups, listeners and even other radio stations kicked in funding and on-air talent.

“It constituted ... a not-often-equaled example of cooperation between an educational radio station and the community it serves,” wrote Burton Paulu, KUOM’s station manager at the time.

Debuting on July 31, 1946, “KUOM for Kids” was awfully interactive for its era. The program “Rhyme Time” started off as a 15-minute segment of poetry readings. “After two or three broadcasts, child listeners were contributing all the program material,” according to “In the Public Interest,” a 1947 report issued by KUOM.

In the 5 p.m. time slot, the station aired “Drawing to Music.” Children were invited to send in art inspired by the music just played. More than 9,400 illustrations poured into the station, which announced winners in three age groups every day. After the epidemic waned that September, much of the children’s art was displayed in an exhibit at the U’s Northrop auditorium.

In addition to “Rhyme Time” and “Drawing to Music,” the station aired a weekly dramatic production, storybook readings and a sports discussion. George Grim, a popular Minneapolis Tribune columnist and radio personality, was credited with proposing “that radio might provide the answer, the means of keeping children happy at home.”

Adopting the radio name Uncle Ray, Grim read comic strips and cracked jokes during the 7 p.m. slot. Come Saturday, a public health professor discussed the epidemic and prevention measures on “Your Health and You.”

The polio epidemic lingered through the summer of 1946, delaying the start of school for two weeks that September. So KUOM producers teamed up with local teachers to offer “School by Air” with shows on hygiene, geography, intercultural understanding and what to expect once school resumed.

“The entire effort shows how the university’s relationship with the public can thrive when its radio station provides a service during a public emergency,” Toov said.

Minneapolis Mayor Hubert Humphrey and parents gushed with appreciation for the station’s efforts during those scary summer days. Calling the run of children’s radio “splendid,” Humphrey said of KUOM: “Your contribution through the facilities of the station to the welfare of our city cannot be overestimated. You have done much to make this serious period in our community life a much more pleasant experience for thousands of young people.”

Helen Motsick, a Minneapolis mother of an 8-year-old, spoke for her fellow parents in a letter Noov unearthed in her research.

Thank you, Motsick wrote, “for the grand job you have done in planning for the children who have been staying home during this epidemic. ... I have called a number of my friends who have children, and they too think you are doing a grand thing to thus think of the children.”

Another state polio epidemic killed 206 and infected nearly 4,000 Minnesotans in 1952, said to be the highest rate among states in the nation. Three years later, Dr. Jonas Salk came up with a polio vaccine. By 1967, Minnesota reported having no polio cases for the first time since health officials began tracking the disease in 1908.

Curt Brown’s tales about Minnesota’s history appear each Sunday. Readers can send him ideas and suggestions at mnhistory@startribune.com. His latest book looks at 1918 Minnesota, when flu, war and fires converged: http://strib.mn/MN1918.